No standardized test for determining the catalytic activity of materials such as activated carbons and chars has been reported. It has been known that carbonaceous chars such as activated carbons have the ability to decompose aqueous solutions of hydrogen peroxide. Tests using this reaction can be used to distinguish chars having different chemical and physical characteristics. These prior art peroxide tests typically involved the use of isothermal volumetric techniques wherein the rate of oxygen evolution was measured for a carbon/peroxide system at constant temperature. These techniques are generally expensive, tedious, and time-consuming, requiring a reasonably sophisticated apparatus to permit reaction of the carbon with the peroxide and measurement of the rate of gas evolution at constant temperature.
An alternative test is to measure the rate of the reaction at a given temperature using calorimetric techniques. However, such tests are sophisticated and require great attention to detail to produce meaningful results. Moreover, because of the difficulty in producing meaningful results and achieving reproducibility, such tests have not been generally recognized as a standardized methodology for rating the catalytic activity of carbonaceous chars.
Accordingly, it is the object of the present invention to provide a test for the measurement of the relative catalytic properties of carbonaceous chars which is inexpensive, simple, flexible, and convenient, and provides meaningful indications of catalytic activity in a relatively short period of time. It is a further objective to provide a test method capable of functioning as a standardized, reproducible methodology.